Abstract: An estimation model of effective bending stiffness for filament-wound composite housing of circular railgun barrel is established based on the 3D composite material thick beam theory. Some effects of beam, such as the three-dimensional strain and warping, are considered in the proposed model. The calculation method of effective bending stiffness of composite beam is used to analyze the bending stiffness of the whole filament-wound composite barrel for railgun. The results are compared with those obtained by laminated plate theory and finite element method. The result shows that the calculated results of the three methods have good consistency for bigger winding angle. The effects of the winding angles of fibers and carbon fibers in different radial positions and the different bore insulators on the bending stiffness of barrel are studied. The research result reveals that the bending stiffness of barrel obviously drops with the increase in winding angle while the winding angle is smaller. The winding angle of inner carbon fiber layers has a great effect on the bending stiffness compared with outer carbon fiber layers. The bore insulator with high density and high elastic module can't always enhance the bending stiffness of barrel.Key

Key words: ordnancescienceandtechnology, 3Dbeamtheory, electromagneticrailgun, barrel, laminatedplatetheory, bendingstiffness